Homebodies - S4-E3
Continuity mistake: When Brass and Grissom are interrogating the stoned nephew, shots of Grissom from the front show him with his head leaning against his right hand and then moving his hand down to the table, then it cuts to a shot from behind and his head is still leaning against his hand. This happens twice during the sequence.
Homebodies - S4-E3
Plot hole: Catherine is picking up the gun in the backyard. It is an unfamiliar weapon. She picks it up by using the loop around the trigger and pointing it towards herself. She then checks the clip, but never checks the chamber.
Answer: He doesn't have the authority to arrest him - when anyone is arrested in the show, a police officer does it. Also he tells Ty that he is going to be submitting his case findings to Ty's insurance company, who would no doubt contact the IRS, who then would have him arrested for fraud etc.